The invention is directed generally to the problem of shoreline erosion, and more particularly to a novel method and system for substantially preventing shoreline bluff or slope erosion due to wave and hydrostatic forces.
The problem of shoreline bluff or slope erosion has long been a matter of concern to littoral landowners who may have erected houses, outbuildings, dock or marina facilities or the like at or adjacent the shoreline. Such erosion can seriously effect such bluffs and slopes, often resulting in the removal of substantial portions of usable land at or adjacent the shoreline to the economic detriment of the landowner.
Especially damaging is the undercutting of such slopes or bluffs due to the wave and hydrostatic forces encountered at or near the shore line. It will be appreciated that substantial undercutting of a bluff or slope can result in the sudden collapse of a considerable amount of the land overlying the undercut slope or bluff portion, resulting in loss and damage to property at or near the crest of the bluff.
The prior art has proposed a number of different methods and/or structures for avoiding such erosion. For example, various systems of jettys and groins may be constructed extending into the water in such a way as to alter the currents and wave patterns so as to avoid or minimize erosion in given areas. However, such alteration of currents invariably results in increased erosion in some adjacent areas of the shoreline and the increased deposition of water borne materials on other adjacent areas of the shoreline. Hence, the use of such groins and jettys is often undesirable when it adversely impacts the littoral rights of adjacent landowners.
Various arrangements of on-shore and off-shore wall structures have also been proposed. Such wall structures may be built partially below the land surface at some point between the high and low tide lines, in an effort to control erosion. In a similar fashion, barriers in the form of containers filled with rock or aggregate material, often referred to as Gabions baskets have been utilized near or in the water in an effort to control the flow and force of water reaching the shore.
Such retaining walls or barriers, Gabions baskets arrangements and the like have generally proven unable to withstand the power of both waves and hydrostatic forces encountered over a period of time. In this regard, both the tide levels as well as wind and wave forces may vary over a period of time. The range of variation in forces encountered makes it difficult to adequately design or place Gabions baskets, retaining walls or other barriers which will be effective under all conditions. Moreover, considerable hydrostatic forces are encountered in the back flow of water from the shore side of these barriers. That is, when waves or tides become of sufficient height to pass over the barriers, considerable pressure is then imposed upon the barriers by the backwash or water attempting to return to the main body of water. Moreover, significant quantities of ground water are often present at or near the shoreline, attempting to enter or reenter the body of water. Hence, such ground water alone, or in combination with the backwash also exerts considerable hydrostatic force upon such barriers or retaining walls or the like.